(Image: Outlander)

Sperm has been on my mind this week. (Note to self: edit this line before filing copy.) I was reading reports about a looming spermageddon.

And I was watching Outlander, which is basically soft porn and some time travel. A recent episode had Claire (a doctor from the future who’s landed in 1740s Scotland) showing her husband Jamie his own sperm through a microscope.

Jamie: “Ah, I see ’em. Wee things with tails swimming about.”

Claire: “Aren’t they marvellous?”.

Jamie: “Aye. Busy wee strivers pushing and writhing. So many of them. Ha.”

He mistook them for the new-fangled “germs”, but they were actually sperms. “I woke up in custody of them this morning,” Claire says (flashback to aforementioned Scottish soft porn).

Back to spermageddon.

Much was made this week of a column in Guardian Australia by Erin Brockovich (yes, that Erin Brockovich) on the possibility of human extinction by 2045 — and it has sparked conversations about shrinking penises, The Taint, and those dwindling sperm counts.

Brockovich’s column was based on a new book by environmental and reproductive epidemiologist Shanna Swan, Count Down.

Publishers describe it as “an urgent, meticulously researched and ground-breaking book about the ways in which chemicals in the modern environment are changing — and endangering — human sexuality and fertility on the grandest scale”.

In short, chemicals including phthalates and bisphenols that are used in everyday products are driving down sperm counts.

“Following the trajectory we are on, Swan’s research suggests sperm counts could reach zero by 2045,” Brokovich wrote. “Zero. Let that sink in. That would mean no babies. No reproduction. No more humans.”

One of Australia’s top reproductive experts, Professor Sarah Robertson — director of the University of Adelaide’s Robinson Research Institute — looked at the data on declining sperm counts and tweeted that it was “pretty compelling” but that a graph showing a steep decline that would probably hit zero in about 2045 had “lots of questionable assumptions and [the] likelihood of straight line decline is low”.

University of Melbourne reproductive biology Associate Professor Mark Green says the 2045 prediction was “a little far-fetched”.

Then there’s this explanation from Swan. Asked whether her words about sperm counts going to zero by 2045 were accurate, she said: “Yes and no.” If the decline was steady, the median sperm count would be zero. Half of men would have no sperm, the other half would have quite low sperm counts.

“However, that’s an extrapolation quite a way from the data, which is risky,” she said.

“It’s particularly risky for biological systems because when you approach a lower limit, the curve will have to flatten out. I don’t actually believe we’re going to hit zero, but if we did, it would be very dire.”

That “prediction” was heavily qualified, and Brokovich indeed just said it “could” happen.

So in this week’s edition of I Call Bullshit, there’s no real bullshit to call out. And the distinction between no sperm at all and a median sperm count of zero got lost in translation.

Still, a headline about the end of sperm hauled a lot of attention on to a really important topic — and I got to gratuitously reference Outlander in the hope that it’ll do the same here.